There exist a number of field bus communication systems, in which various members are arranged in direct vicinity, such as on a rack. For example, in a serial real time communication system (such as SERCOS) application, a master and slaves are centrally arranged. The members are connected to one another by means of common field bus communication devices, such as via Ethernet in SERCOS III applications.
As conventionally known (see, for example, Wikipedia article entitled “SERCOS interface”), signals and commands sent between control modules in industrial control systems must be coordinated. Tight coordination is sometime required, and especially in applications requiring motion control. Examples of equipment requiring tight coordination include metal cutting machine tools, metal forming equipment, assembly machinery, packaging machinery, robotics, printing machinery, and material handling equipment. The SERCOS interface standard is an international standard for digital motion control buses that interconnect, for example, motion control devices, drives, input/output devices, sensors, and actuators for numerically controlled machines. SERCOS, for example, provides for high-speed serial communication of standardized, closed loop, real-time data.
In the central adjacent arrangement of a number of members of a field bus communication system, there exists a problem in that the mutual connection of the members by means of conventional field bus physics or hardware requires substantial and fault-prone wiring in limited space.